>> Is it really my responsibility to call them but not that of its
>> upper RIR, ie LACNIC?
Yes and no. It is LACNIC's responsibility in a moral sense; they have
been granted a resource, and with authority over any resource comes
responsibility for its use.
However, Internet governance is severely broken. Those who need to
impose that responsibility (IANA/ICANN) refuse to, and few (no, AFAIK)
RIRs are sufficiently ethical to assume it on their own. So in a
pragmatic sense, it is nobody's responsibility.
Like any system in which responsibility and authority are severely
mismatched, this is not sustainable. However, the net is robust enough
that it's taking several years for the abuses to grow to the point of
systemic collapse. (It's coming, though. I recently dropped by a
university I used to work at, and apparently there are big voices
arguing for a totally off-the-net private email system, simply for the
sake of having working internal email. That's right, the abuses have
grown to the point where email connectivity to the net has about equal
positive and negative value.)
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